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arXiv · 1408.3109

Gravitational entropy of cosmic expansion

Roberto A. Sussman
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Abstract

We apply a recent proposal to define "gravitational entropy" to the expansion of cosmic voids within the framework of non-perturbative General Relativity. By considering CDM void configurations compatible with basic observational constraints, we show that this entropy grows from post-inflationary conditions towards a final asymptotic value in a late time fully non-linear regime described by the Lemaitre-Tolman-Bondi (LTB) dust models. A qualitatively analogous behavior occurs if we assume a positive cosmological constant consistent with a $Λ$-CDM background model. However, the $Λ$ term introduces a significant suppression of entropy growth with the terminal equilibrium value reached at a much faster rate.

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Roberto A. Sussman. 2014-08-13. Gravitational entropy of cosmic expansion. https://doi.org/10.1002/asna.201412077

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